1. Field of the Invention
This invention relates to optical image projection devices for superimpositionally projecting a scanned light beam, such as a laser beam, upon photographic subject matter within the field of view of a camera. More particularly to indicate a field of view of a camera or some portion of that field of view such as an optical frame that a photographer has chosen.
2. Discussion of Prior Art
It is known to use a variety of media to record a photographed image, such as:
a photographic emulsion upon a film base sensitive to visible radiation of the electro-magnetic spectrum, PA1 a photographic film photosensitive to invisible radiation of the electromagnetic spectrum, PA1 a photographic negative image film, PA1 a photographic positive image film, PA1 a tape media employing ferro-magnetic means of recording electronic impulses, PA1 a solid disc media employing a laser beam means of recording digital electronic impulses, PA1 aforementioned media with capabilities of recording gradations of gray, and PA1 aforementioned media with capabilities of recording hues of color. PA1 a dimensional width of a photographic film, PA1 a thickness of a photosensitive emulsion applied to film media, PA1 a size of a perforation punched into a film, PA1 a number of perforations per inch punched into a film, PA1 an amount of ferro-magnetic material applied to a tape media, PA1 a photosensitivity of a photographic film, PA1 a grain quality of a photographic film emulsion commonly ascertained by the quantitative value of a crystalline chemical material within the emulsion, and PA1 a laser-disc media. PA1 a lens system with variable focal length, PA1 a lens system of specific focal length, PA1 a shutter system, PA1 an iris, PA1 a pressure plate, PA1 an aperture gate, PA1 a viewing system, PA1 a film advance mechanism, PA1 a film rewinding mechanism, PA1 a camera body, PA1 a flash lighting system, and PA1 a hard matte. PA1 a color of the image, PA1 a dimension of the image, PA1 a width to height aspect ratio of the image, PA1 a subject matter included in the photographic print, PA1 a subject matter added during optical printing, PA1 a subject matter masked during optical printing, PA1 a subject matter deleted during optical printing, PA1 a subject matter excluded from optical printing, PA1 a light intensity of the photographic print, and PA1 a light intensity of a part of a photographic print. PA1 superimposition, PA1 beam splitting image convergence, and PA1 matting. PA1 a chyron effect, PA1 a chroma key effect, PA1 a paint box effect, PA1 a frame expansion, PA1 a color change, PA1 an editing choice, and PA1 a duplication. PA1 a television broadcast, PA1 a screen projection, PA1 a wide screen projection, PA1 a 35 mm projection, PA1 a 70 mm projection, PA1 a vistavision theatrical presentation, PA1 an omni-max theatrical presentation, PA1 an Imax theatrical presentation (Image maximization), PA1 a 35 mm anamorphic squeezed projection, and PA1 a 35 mm anamorphic non-squeezed projection.
It is known to use a variety of dimensional and material formats in the manufacture of image recording media, such as:
It is known to use a variety of physical components to build a recording camera, such as:
It is known that the variables concerning photographic recording media, a camera's physical hardware components, and camera accessories combine to produce a recorded image of specific aspect ratio and constant area size commonly referred to as the full aperture image.
It is known in motion picture photography and still frame photography that a full aperture image is an image recorded on photographic film without the use of any delimiters, such as a hard matte. The size of a full aperture image is commonly determined by the physical dimensions of an apertured plate. For instance, a camera with an aperture size of 0.976".times.0.437" will record a full aperture frame image that is 0.976".times.0.437" on the film emulsion.
It is known that video recording technology incorporates the use of electronic sensors to translate light ray bundles into electronic impulses which can then be stored on video recording media such as ferro-magnetic tape. The image size of a video recording is usually limited by the physical arrangement of the sensor array and the light gathering capacity of the camera's optics. Video images remain flexible in dimensional size even after recorded upon a media because of the ease of manipulating electronic impulses. However, for the purpose of explaining the invention the term "full aperture image" shall apply to the image striking the photosensors of the video camera. This term shall apply similarly to alternate forms of photography that do not employ a photographic film emulsion for recording.
The term "full aperture image" is applied to a recorded photographic image of an object and is used to define the maximum possible area size of an image produced by any specific camera hardware configuration.
In film photography the process of generating a replication of a full aperture image is commonly referred to as printing. An optically printed replication of the full aperture image is often referred to as a photographic print. In motion picture photography the final photographic print, commonly called the answer print, passes through several intermediate stages of printing commonly called; a work print, a rush print, a trial composite, an interpositive, or an optical print. These prints are used by various individuals for various purposes. A film editor utilizes a work print for initial trial editing purposes. A rush print is used principally for viewing purposes to ascertain mistakes in the various elements of photography. A trial composite is used to balance color throughout the film. An interpositive is utilized to create duplicates. An optical print is utilized to add special effects photography. In still photography the photographic print can exist in various forms as it may be printed on a variety of media, such as a photographic print paper or a transparent media.
It is known that a photographic print can vary radically from the full aperture image from which it was generated. Many variables can affect the photographic print during optical printing, such as:
It is known that processes applied during the course of printing can affect the resulting photographic print, among these are:
Additionally photographic images are commonly transferred to magnetic media for purposes that include:
During transfers between recording mediums the optical frame can shift slightly due to accidental misalignment or due to deliberate manipulation.
The term "photographic print" is applied to a complete or partial replication of a full aperture image and is used to define any possible duplication, partial or complete, of a full aperture image.
The perimeter of the area containing the photographic print is commonly referred to as an optical frame. A photographic print may be an exact duplicate of the full aperture image or it may be a partial replication of the full aperture image.
The term "optical frame" is applied to a recorded photographic image and is used to define the perimeter of an area containing a photographic print of a full aperture image.
An optical frame containing a photographic print is commonly rectilinear in form and referred to by the dimensional aspect ratio of its width to height. In motion picture photography the theatrical presentation of a film can be projected utilizing a variety of aspect ratio formats. Typical aspect ratios utilized in 35 mm film theatrical presentation are: 1.37:1, 1.66:1, 1.75:1, 1.85:1, and 2.4:1. Typical aspect ratios utilized in 70 mm theatrical presentation are: 2.2:1, and 2.4:1. A typical aspect ratio utilized in television broadcast is 1.33:1; however, a television broadcast format is not truly rectilinear having rounded corners.
It is known that a number of different presentational formats exist, such as:
Each of these presentational formats may be considered by photographers, key film technicians, and production personnel during photography. Consultations and discussions among them concerning appropriate framing often result.
When a photographic image is presented via a number of differing presentational formats, the optical frame may undergo substantial changes in terms of a width to height dimensional aspect ratio; consequently, in the motion picture industry it is commonplace for key members of the film crew to discuss the multiple optical frames of a single full aperture image that may undergo theatrical or broadcast presentation. The numerous permutations of possible optical frames compounds the difficulty of communication concerning an optical frame or the subject matter contained within it.
A cinematic director of photography may refer to the 1.33:1 aspect ratio television broadcast optical frame when relating concerns about the positioning of the microphone to the sound recording engineer; however, he may simultaneously instruct a camera operator to frame the action using the 1.85:1 aspect ratio of a common motion picture optical frame, then assure a producer that certain subject matter elements are being recorded in motion picture full aperture frame image even though they are not included in the 1.85:1 optical frame.
In still frame photography the photographic print can also be very different in size from the full aperture image and can include only a portion of the image recorded on film. Still frame photographers commonly call this process cropping the image. This cropped image represents an optical frame within the recorded image. This optical frame is often difficult to communicate since it is not represented in the viewfinder of the camera. Photographers typically will point to the subject matter or indicate by verbally describing where an optical frame falls within the subject matter. Sometimes, during fine adjustments, it is even necessary for the photographer to walk from the camera to the subject matter so as to physically indicate a boundary of an optical frame he has envisioned.
The difficulty of communication concerning an optical frame is also compounded by the sheer number of individuals concerned with it, for instance:
A 1st assistant cameraman is responsible for altering the focus of the lens to follow the action being photographed. Oftentimes the follow focus occurs as an actor or an object enters a scene. Without knowing the precise boundary of the optical frame being considered, a critical moment in the action may be left out of focus. The same considerations extend to the manipulation of the focal length of a lens, commonly called zooming.
A gaffer concerned with lighting cues is dependent on knowing whether the action that motivates the lighting cues is in frame. He may also be concerned with the physical placement of a lighting instrument encroaching on an optical frame.
Costumers, set dressers, make-up artists, hair stylists, and stand-by painters, are examples of technicians concerned with the subject matter being photographed. Commonly these individuals have no reference display that indicates the optical frame and, consequently, they are not aware sometimes that the subject matter of their concern is being photographed.
Aside from the technical crew, there exist a number of individuals without direct responsibilities o the shooting set; yet, these individuals are concerned with the photographic framing. Many of these individuals are involved in post-production work such as editing, special optical effects, composite matte photography, or animation overlay cels. Oftentimes, they visit the shooting set to ascertain specific information that may help them prepare for their work. To obtain that information they often must address the photographer or reference the reflex viewing system of the camera, a time consuming distraction for a busy photographer.
Actors are constantly wondering whether they are in frame. Thousands of shots have been ruined by an actor inadvertently drifting out of frame. Occasionally, a close-up shot of some small action requires a precision of movement within an optical frame; however, without a reference guide, trial and error experiments are the normal procedure.
Thus, the general problem that this invention addresses is the long felt need for a device that would enable a film worker to discern an optical frame by direct visual reference, thus facilitating communication regarding an optical frame and the subject matter contained within its border.
Heretofore, viewing systems have been employed to facilitate communication between a photographer and other film workers. A viewing system allows a photographer to reveal the image he intends to record to others; however, to do so he must remove his eye from the eyepiece to allow others to look into the eyepiece. Two types of viewing systems are commonly used for this purpose: a reflex viewing system and a non-reflex viewing system.
A non-reflex viewing system commonly utilizes a secondary lens system. It is aligned parallel to, but separated from a camera's optical axis. The consequent parallax effect produces a viewing image that will differ slightly from the image that will be recorded.
A reflex viewing system utilizes reflective optical elements to transmit a photographic image directly to an eyepiece. A reflex system's optics are precisely aligned with the camera's optical axis; consequently, the image seen by a viewer looking into the eyepiece is identical to the image that will be recorded by the camera.
A ground focusing glass is a removable optical element of the reflex viewing system. It is located along the optical axis of the reflex viewing path at the focal plane of the camera lens. A ground glass is commonly demarcated with lines or etchings that correspond to optical frames of specific aspect ratio. Ground glass plates are available with a wide variety of indicated optical frames and can be interchangeably mounted within the camera. These framing reference lines help a camera operator to align specific subject matter within the demarcated optical frame; however, to discern the optical frame via ground glass demarcations a photographer must be looking through the reflex system of the camera. If a photographer looks directly at photographic subject matter he has no reference frame to guide him. Furthermore, should a photographer wish to communicate the exact optical frame he is considering he must allow another individual to look through the viewing system of the camera.
Video cameras can be integrated with the reflex viewing system of photographic cameras to produce an image on a remote monitor. Coaxially aligning the video camera with the photographic image is commonly accomplished by means of a beamsplitter. A beam splitter is an optical element that replicates an image by partial reflection. The replicated image is diverted to the video viewing system's electronic sensors. The sensors convert the optical image into electronic information which is sent to a remote monitor. At the monitor the information is converted into a video image which can be viewed without having to reference the eyepiece of the camera.
Video viewing systems offer two advantages over reflex viewing systems. The photographer is freed from the burden of sharing the reflex viewing system with others and video monitors allow multiple simultaneous viewers; however, the advantages of video viewing systems have to be balanced with the disadvantages of a video monitor's picture. The lighting is distorted, imaging perspective is severely reduced, and the image presented to the viewer is a two dimensional representation of three dimensional subject matter.
The hardware employed by video viewing systems imposes additional limitations. Oftentimes, because of the physical bulk of a monitor, the monitor is located in a remote area, reducing the photographer's ability to communicate with those observing the monitor. Video monitors often need cabling systems connecting them physically to a video tap which is connected to a camera. Monitor cables are unwieldy, bulky, entangling and often awkwardly restrict camera movements or the movements of a camera operator.
A further disadvantage of a video viewing system is that one cannot view a monitor and simultaneously view directly the subject matter being photographed.